Sighting device.



'E- A. 'KELSEY.

SIGHTING DEVICE.

PLlCATlON FILED OCT. 3. 1914.

Patented July 13, 1915.

J ploying should force the ball shaped portion of the p EDGAR A. nnrsnir, or MOUNT vnnnon, NEW YORK, assienon 'r'o Tran NATHAN nanuraoruninaooivrrnnr, or NEW YORK, n. it, A conronnrron or new YORK.

srenrine DEVICE.

menace.

Specification of Letters Patent. Pa-ig ited J l 13 Application filed October 3, 1914. Serial 110.86%,825.

TooZZ whom it may concern: 1

Be it known that I, EDGAR A. KnLsnY, ,a citizen of the United States, residing at Mount Vernon, in thecounty' of Westchester and State'of New York, have invented certain new and useful Improvements inSighting Devices, of which the following is a specification.

This invention relates to a sighting device for lubricators or similar apparatuses provided with openings throughwhich the internal condition of such may be observed and is an improvement, onthe sighting device shown in my application for Letters Patent filed April 21, 1914, Serial. No. 833,384, and its novelty consists chiefly. in the construction of the means adapted to compress the packing as will be more fully pointed out hereafter.

The purpose of my invention is to preclude the possibility of a leak in the form of the device covered by my above mentioned application, when the high pressure, usually prevailing inside of apparatuses emmy improved sighting device,

sight glass through the packing surrounding the same, and to that end consists in the provision within the follower compressing the packing, of a seat, against which the ball shaped portion of the glass would form a pressure tight seat of suflicient width to prevent any fluid or gases escaping into the atmosphere.

1n the accompanying drawings Figure 1, is an end elevation of a portion of an apparatus such as a lubricator, provided with a casing and sight glass and a follower embodying the preferred form of my invention. Fig. 2, is a transverse vertical section on the plane of the line 22 in Fig. 1, and Fig. 3, is a section similar to the one shown in Fig. 2 with the glass forced through the packing by internal pressure and seated against the follower.

Like characters of reference denote similar parts throughout the several views.

In the drawings 10 is the body or frame of the device to be provided with the sighting elements. It is suitably apertured and the periphery of such apertures is preferably internally threaded to receive the casing indicated at 11, and which is externally threaded at its inner end to fit within such aperture. The casing is provided with an inturned annular flange 12. which is beveled to form a seat for the rounded surface of the s ght glass as willpresently be described and ls-reverted at 1 1 to form a second seat adaptedto be engaged by a packing l5r'estng against the same. i

Arranged within the casing is the sight glass comprising a central body 16 made" of atruncated sphere and? which body is prov ded with a cylindrical extension; 17 on one slde, loosely fitting within the casing, and a secondcylindrical extension 18 on the other side. The beveled sea-t 18 0f the casing; is preferably made so that its outermost edge is within the limitsof the circumsonibing' cyl lnder of the spherical portion of the glass.

Thus far the device is essentially the same as the one embodied in my application for Letters Patent, filed April 21, 191-1, Serial No. 833,384 and for convenient reference the same numbers have been used to denote the difi'erent parts. With a device of this kind I am using the improved packing and seating means hereinafter described.

19 is a follower, externally threaded at 21, to engage the internal threads of the casing and provided with an inwardly projecting annular flange 20 adapted to press against the packing 15.

22 is a central interior portion of the follower of such diameter as to loosely fit over the cylindrical extension 18 of the sight glass. 1

23 is an annular recess at the innermost interlor portion of the follower, and of hollow truncated spherical shape adapted to closely fit the spherical central portion of the glass and to form a pressure tight seat thereon, substantially throughout the entire depth of the recess. The outermost interior part of the follower is provided with a recess 24:, polygonal in shape, for the purpose of receiving a suitable socket wrench for tightening the follower against the packing.

It can readily be seen that if an excess of internal pressure should force the spherical portion 16 of the sight glass through the packing 15, this spherical part will be forced against the walls of the recess 23 and will form a wide pressure tight joint thereon as clearly illustrated in Fig. 3, thereby effectively preventing leaks.

The central interior portion 22 of the follower is made of such length as to prevent the projecting of the cylindrical extension 18 w an inwardly projecting flange adapted to i1npinge against the packing, and having an annular recess at its innermost interior part, said recess being rounded so as to conform closely to the contour of the rounded central body portion of the glass.

2. A follower for a sighting device comprising an externally threaded portion, a cylindrical extension on one side thereof, having an annular recess in the shape of a zone of a hollow sphere within the said cylindrical extension, the follower having a cylindrical bore through its interior connecting the said annular recess with a recess, polygonal in shape, on the opposite end of the said follower, in combination with a casing, and a glass with a rounded central body portion, an internal beveled seat within ,the casing adapted to contact with the said body portion of the glass, and a packing interposed between the rounded body of the glass and the casing, the said rounded central body portion of the glass closely conforming to the shape of the said annular recess within the cylindrical extension of the follower, the said casing being internally threaded to engage the externally threaded portion of the follower.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

EDGAR A. KELSEY. Witnesses:

LEOPOLD KAssANDEn, WALTER E. WOLLHEIM.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents.

' Washington, D. G.

at I 

